Keywords physical activity - counselling - childhood cancer - exercise - re-integration - health behavior
Schlüsselwörter körperliche Aktivität - Beratung - pädiatrische Onkologie - Bewegung - Wiedereingliederung - Gesundheitsverhaltenpublished online 2024
CAYASs Children, adolescents, and young adults
PA Physical activity
HQ Headquater
PAC Physical-Activity-Counseling
LLE Late and long-term effects
PE Physical Education
NAOK Network ActiveOncoKids
POC Pediatric oncology centers
Background
The medical guideline on the promotion of physical activity (PA) and exercise in
pediatric oncology emphasizes the necessity to implement the “National
Recommendations for Physical Activity” for affected children, adolescents, and young
adults (CAYAs) as its primary recommendation [1 ]. Despite an increasing number of exercise initiatives at pediatric
oncology centers (POC), most local structures are currently not including a
comprehensive Physical-Activity-Counseling (PAC) service tailored to the individual
needs (in-/outpatient, at home, during follow-up and survivorship, in palliative
care). In Germany, about 2,200 children and adolescents aged<18 years are newly
diagnosed with an oncological-hematological disease annually [2 ]. Despite 5-year survival rates
exceeding>80% [3 ], cancer suddenly
and permanently changes the lives of CAYAs. The disease and medical therapy are
affecting the entire family system, including high psychological burden and
unexpected organizational, financial, and bureaucratic hurdles [4 ]. Newly diagnosed young adults,
planning their future, including career entry, partnership, autonomy and possibly
the desire to family formation, are facing the fight against a life-threatening
disease, with late and long-term effects (LLE) often persisting throughout
adulthood.
Many patients suffer from common side effects, repeating inpatient stays and
protracted hospitalization resulting in a reduced quality of life [5 ], limited social activities and school
attendance [6 ] as well as reduced
cardiopulmonary fitness [7 ], and muscle
strength [8 ]. After cessation of
treatment, some patients suffer from LLE such as weight changes [9 ], polyneuropathies [10 ], osteonecrosis [11 ], balance disorders [12 ], and movement restrictions due to
prosthetic devices [13 ] or fatigue [1 ]. They show a lower level of fitness
and health during follow-up compared to healthy peers [14 ]
[15 ]
[16 ]. An adapted exercise
programme can also positively influence all phases of therapy and counteract lacks
of physical-mental resilience and performance. Targeted exercise interventions have
the potential to reduce negative impact of physical inactivity on health and to
support age-appropriate development of physical and coordination skills and social
and sports participation. Thus, optimal conditions to return to former (sports)
structures or, if necessary, to access new adapted PA programme through positive
exercise experiences adapted to LLE are provided.
Therefore, many POC strive to implement exercise programme, including counseling from
diagnosis onward. In Germany, 33 POC (55%) currently offer exercise of varying
extents, which are bundled at the Network ActiveOncoKids (NAOK) headquarters (HQ;
[17 ]). However, the majority of
patients still do not receive supervised exercise interventions or support in
practices of daily life, such as q.e. cycling [18 ]. Families, coaches and physical education teachers however are not
qualified to take on this role. Situations like inexperience regarding exercise
pre-diagnosis, social disadvantages and/or severe psychological burden, an
unsupportive social environment, rural surroundings or complex LLE might require
particularly intense support. The NAOK [17 ] was founded to especially empower these groups to participate in PA
programme and to support POC in establishing an exercise and counseling programme
for all CAYAs throughout Germany. Since 2019, NAOK-HQ has been focusing on raising
awareness of the relevance and prospect of its POC in a multidisciplinary team, and
on implementing and evaluating exercise as effectively as possible. In addition to
counseling, the NAOK-HQ and the NAOK steering group are in charge of structural and
scientific topics such as writing medical guidelines [1 ], clinical consultations and public
relations [17 ]. In 2019, NAOK has been
established as working group with statutes and membership applications within the
German medical Society for Pediatric Oncology and Hematology.
This article describes the NAOK-PAC concept, its development and the first 200
included CAYAs patients and survivors.
Aims and structure of physical activity counseling (PAC)
The NAOK-PAC addresses CAYAs with all cancer diagnoses and ages and their
families to find available and accessible PA programme. The underlying principle
of the counselling is an individualised approach, taking account of local
circumstances and involving local coaches and sport clubs if appropiate.
Oncology-specific PA projects, such as post-amputation or transplantation
activity events are arranged. Another focus is on (re)integration into Physical
Education (PE).
Contacting the network ActiveOncoKids (NAOK)
The NAOK-HQ promotes the PAC in three ways: (1) proactive contact, (2) medical
staff contact, and (3) event-based contact. Contact attempts refer to all
individuals who have directly contacted the NAOK-HQ (1). This includes the
homepage (https://www.activeoncokids.de/ ), links to associated websites (e. g.,
German Cancer Aid; Kinderkrebsinfo), social media (Instagram, Facebook) and
print materials available at clinics:
Another way of connecting to the NAOK-PAC is via local clinic staff aware of the
NAOK (2). A POC can contact the NAOK-HQ via phone, e-mail, or in person. A third
option is the presence of the NAOK-HQ at events (3) (e. g., meetings of the
NAOK, nationwide camps, seminars, self-help groups).
Further developments
After a decrease in contact requests during the COVID-19 pandemic, its number has
been growing steadily, using social media channels and new print materials, and
showing a strong increase upon attending patient events. After personal contact
with a clinic’s multidisciplinary team, the number of inquiries increases, as
the providers actively recommend NAOK-PAC.
Material und Methods
Description of the NAOK physical activity counseling concept
The NAOK-HQ uses a consulting model ([Fig.
1 ]) that is being continuously developed as an agile system concept
based on the growing experience gained in NAOK consultations. It includes the
following five phases: preparation, anamnesis, organization, test phase, and
feedback. At three measurement points (t0 =anamnesis;
t1 =after four weeks; t2 =after 16 weeks), data is collected
on goal setting and completion as well as on subjective perception of exhaustion
and stress.
Fig. 1 Cooperation partners and supporters of the NAOK; the colors
were chosen arbitrarily, Quelle: Netzwerk ActiveOncoKids, https://www.activeoncokids.org . [rerif].
Phase 1 – Preparation
An appointment-based telephone or in person meeting is held. If contact is
made through a parent, the person concerned also takes part in the meeting.
Children aged>8 years are always participating. At the beginning,
information is provided on the structure of the NAOK including the funding
by the German Cancer Aid, data protection and the joint working basis. The
objective of the latter is not to meet new requirements as participation in
the programme is entirely voluntary and is primarily based on the patient’s
needs [19 ].
Phase 2 – Anamnesis
The anamnesis includes six categories:
Basic data,
Disease-specific data,
Exercise-specific data,
Objectives and needs of the CAYAs
Subjective evaluation of physical/mental exhaustion and resilience at
three measurement points (t0 -t2 ; since
consultation no. 151).
If appropriate, patients are asked to record a video, showing them in action
(e. g., gait after prosthetic fitting, balance status after brain tumor,
severity of hemiparesis, degree of obesity), and to provide the medical
letter.
→ The QR code links to the anamnesis questionnaire.
During the assessment, possible sports are weighed up as to risks and
benefits and logistic aspects (accessibility, time required, personal
requirements) are addressed [20 ].
Phase 3 – Organization
In the organization phase the aims identified by CAYAs (and parents) are
considered individually and approaches to participation in PA programme are
presented. The pre-collected information on a structural and personal level
as well as the cooperation partners ([Fig. 1 ]) is integrated. Soon after the anamnesis, all parties
involved receive an e-mail, summarizing the discussion, formulating the next
steps taken by the advisor and providing basic information (social media,
general training recommendations, empirical education projects suitable for
the target group, etc.). A follow-up email offers targeted and
individualized exercise programme, includes a request to review the PA
programme, and prompts feedback on what recipients consider interesting and
relevant. There are three different organization phase procedures, depending
on the setting of the chosen PA.
Procedure in the setting of sports clubs: Strengthening of
self-confidence, social skills, and physical health
Contacting the sports club.
Involving local NAOK clinics and NAOK members` experience.
Contacting coaches of appropriate groups.
Checking whether the offer, the pedagogical concept, and the group
performance level matches the needs.
Arranging a test training.
Informing the coaches on any possible experience, restrictions, and
the NAOK’s support.
Procedure in the PE setting: Participation of participation and ensuring
weekly physical activity session
Involving the parents, an online meeting is scheduled with the
invited PE teacher to discuss (re)integration into PE, with the
option for the parents to join or not.
Including NAOK expert on PE issues.
Examination of the problem from all perspectives.
Developing solutions jointly, e. g., teacher training, providing
relevant information brochures, involving expert staff who promote
inclusion or specific sports recommendations from the medical
doctors.
Procedure for cross-setting goals: Mitigating LLE of medical therapy and
participation as well as increasing self-efficacy
Organizing, e. g., horse riding therapy, swimming courses, personal
training, physio- or occupational therapy.
Involving foundations/associations in case of family’s financial
overload.
Creating individualized training programme by the NAOK-HQ.
Establishing contacts and offering education to exercise therapists
by the NAOK-HQ.
On request, psychosocial support of exchange with other affected
persons and experts, establishment and expansion of self-help
groups, advice platforms.
Improving everyday mobility, e. g., by providing opportunities to
attempt barrier-free cycling and receive tailored consultation from
NAOK members.
Notice the offers of NAOK centers (Ruhr, North, Bavaria,
Rhine-Main-Neckar, central Germany), the internal NAOK clinics, and
other cooperating partners and institutions.
Communicating information access points (homepage, flyers, etc.) and
contact persons.
Phase 4 – Test phase
During the test phase, those CAYAs become familiar with the sports programme
without obligation, implement the ideas developed, test the infrastructural
situation for feasibility as well as compare general conditions (group size
and composition) and the objectives with their own needs. Depending on the
availability of the contact person at the home location and the
implementation options to be advised, a few days to several weeks can pass
between the initial meeting and the start of the test phase.
Phase 5 – Feedback
Both after four (t1 ), 16 weeks (t2 ) and after the trial
phases’ start, the NAOK-HQ initiates contacted via phone: The actual status
and the subjective assessment of resilience and exhaustion are evaluated by
a standardized questionnaire compared to the information obtained from phase
2 (t0 ; anamnesis). If the intervention from phase 4 turns out to
be inappropriate, the research restarts and a re-entry to phase 3
begins.
Results
Evaluation of the first 200 counselings
From June 2019 to March 2024, a total of 200 CAYAs were counseled by the
NAOK-PAC. [Fig. 2 ] describes the
collective in terms of gender (a), age (b), therapy phase (c), diagnosis (d) and
place of residence (e). A small number (3%) made use of the PAC from abroad.
Fig. 2 Characteristics of gender (a ), age (b ),
therapyphase (c ), diagnosis (d ) and localization
(e ) at the time of the initial contact (Abbreviations used:
“Other cron. Dis. – Other chronic diseases”; Acute ther. – Acute
therapy”).
Recruitment
Two thirds (65%) were recruited via POC, who, informed about the counseling via
NAOK flyers. 17% were recruited at events for patients and survivors and 18%
found out about the NAOK-PAC independently via internet research.
CAYAs Characteristics
The percentage of males was 10% higher compared to females ([Fig. 2a ]). The five defined age
groups (<6, 6–10, 11–15, 16–18,>18 years) were represented with at least
8% (N=15) PAC requests each ([Fig.
2b ]). 66% of the NAOK-PAC ([Fig. 2c ]) took place during follow-up care. 28% were receiving acute
therapy or long-term therapy during initial anamnesis. The “other” group
includes CAYAs in palliative situations (1%), with other chronic diseases (5%),
and with unknown diagnoses (2%). The largest group consists of CAYAs with
serious LLE ([Fig. 2d ]). Half of
those were affected by a brain or bone tumors. Families whose children had
chronic diseases such as familial mediterranean fever, cystic fibrosis and renal
insufficiency also requested counseling at greater intervals. Representing 4% of
the total collective, the group is allocated to “other”. [Fig. 2 ] shows the distribution of
requests by home (federal) state at the time of PAC.
Feasibility
All persons interested received a PAC including anamnesis and general exercise
recommendations. One person died during the 3th phase, N=3 people suffered a
relapse and could not complete phase 4 and 5. No drop-out occurred.
Aims
Frequently defined targets (multiple answers possible) were “improving health”
(88%) and “improving fitness” (75%). “Gaining social contacts”, “finding a
sports club”, “optimizing leisure activities” and “participating in camps” were
also wished for in the NAOK-PAC (50%).
Case-related results
[Table 1 ] indicates that all PAC
received basic information, with over half of CAYAs connected to a local NAOK
center for follow-up PA programme. Almost half of CAYA contacted NAOK-PAC for
new sports clubs. Around 20% were interested in dancing, another 20% in sports
like badminton, table tennis, and soccer, with a fifth interested in martial
arts and self-defense. Ten patients with pronounced LLE such as severe loss of
balance, ataxia or severely limited physical resilience expressed the desire to
PA in a group with people of the same age. Twelve people affected were connected
to inclusive offers. 13 PAC took place in rural regions. Eight of CAYAs were
connected to an online service and the adult family members received intensive
coaching from the NAOK-HQ so that they could carry out the training
independently.
Table 1 Outcome of the first 200 network ActiveOncoKids
(NAOK) Physical Activity counselings.
Case-related results
N
%
Basic information
200
100
Connection to cross-clinic NAOK centers
112
56
Connection to a sports club
80
40
Dancing
14
17,5
Badminton, Tabletennis and Soccer e. g.
17
21,2
Martial Arts and Self-defense
15
18,8
Watersports (Rowing, Stand-up-paddling)
16
20
Water-based exercise (diving and rescue swimming)
18
22,5
Connection to specific projects
70
35
(Re)connection to a pediatric oncology centers
30
14
Creation of a training concept by the NAOK
30
14
Connection to NAOK-members and -experts
18
9
Conversations with Physical Education teachers
18
9
Case studies
[Table 2 ] shows six case studies
that varied in specific problem, age, gender, diagnosis, therapy phase, LLE,
recruitment, targets, solution strategies and results.
Table 2 Six case studies to exemplify case-specific
challenges and approaches to netweork ActiveOncoKids (NAOK) Physical
Activity counseling (PAC).
Case
I
II
III
IV
V
VI
Specific problem
Very anxious family; rural area; lack of sports programme in
the Physical Activity counseling
No previous experience in engaging in physical activity;
immunosuppression
Rural area; anxious and insecure in behavior; comparison of
athletic abilities before and after diagnosis
Participation in physical activities only possible in a
wheelchair
Lack of a contact at pediatric oncology centers
Lack of support by the family and social environment
Age / ♀ ♂
4 / ♂
6 / ♀
9 / ♂
12 / ♂
17 / ♂
23 / ♀
Diagnosis
Leukemia
Brain tumor
Wilms‘ Tumor
Bone tumor
Lymphoma
Brain tumor
Therapy phase
Acute therapy
Acute therapy
Follow-up care
Follow-up care
Long-term therapy
Follow-up care
Recruitment
Internet research by a family member
Printed materials in the clinic
Recommended by befriended family
Assignment via rehabilitation clinic; contact through
Physical Education teacher
Recommendation by senior physician of the treating clinic (no
NAOK cooperation)
NAOK presence at a young people’s seminar
Side-, late- and long-term effects
None
Impaired balance; slight retardation
Reduced physical performance, especially coordination
Amputation and uncertainty in the use of the prosthesis after
hemipelvectomy
Fatigue and physical exhaustion
Severe visual impairment; impaired balance; depression and
fatigue
Target
Maintenance of physical performance and joy of movement
Improvement of motor skills; joy; ideal promotion of physical
activity
Enjoyment of movement despite reduced fitness with peers;
Strengthening resilience through sports (as already known as
a resource prior to the disease)
Optimal support for participation in Physical Education
Create the physical basis for participation in a five-day
mountain tour as part of the final year; recovery of
physical disability
Making social contacts; Strengthening of self-esteem;
mobility; Improvement of physical performance
solution strategies
Contacting the pediatric oncology centers and
requesting a prescription for exercise therapy from
the attending physician
Online training of the physiotherapist in charge
Establishing the connection to online programme
InterActive (financed by DuMusstKämpfen!);
Repeated consultations about integrating physical
activity into everyday life
Provision of motivational movement videos
Establishing a connection to cooperating university
and mentoring by a student, who offers an at-home
programme once a week
Connection to ambulance of pediatric oncology
centers
Connection to cross-clinc NAOK center incl. climbing
classes, skiing trip and weekly sports group
Integration of the NAOK expertise of the teacher and
handing-out of leaflet and further literature
Integration of the rehabilitation and disabled sports
association
Attempt to incorporate an integration assistant
Request for further training on the topic “wheelchair
integration” for teachers with this question in
their own federal state at the universities’ sports
institutes, the teachers’ sports association, the
state sports association, the disabled sports
associations, the Ministry of Education and Cultural
Affairs, initiatives for people with amputations
NAOK-expertise and contact to Faculty of Sport
Science
Rearch for and training of a personal coach
Clarification of funding concept by a foundation
Connection to and integration of various events,
projects, programme and activities in the context of
physical activity
Finding a local club
Being contactable and answering questions
Relaying to NAOK-experts for bike advice and
testing
Results
Subjectively assessed improvement in fitness state due to
1–2x/week attending exercise programme at hometown
physiotherapy practice
1x/week Attending online sports programme with
NAOK-sports scientist
Regular use of the NAOK-YouTube-Channel
Reduction of pressure and anxiety regarding the intensity and
frequency of movement during acute therapy through telephone
conversations and literature recommendations
Improved fitness level and maintenance/increase of
joy of movement
Regular participation in movement sessions in a
pediatric oncological context including interaction
with children who were also formerly ill and their
parents
Gathering of experiences by moving in outdoor sports
areas such as water, snow, and climbing wall
Strengthening of self-confidence
Finding new friends
Improvement of fitness level
Participation in nationwide flight project with the
LSC Leverkusen and flight experience
Offer by the disabled sports associations to organize
a wheelchair basketball day for the class to
facilitate understanding among classmates
Agreement that the teacher may contact the NAOK
headquarters with specific questions regarding the
adaptation of the curriculum
Participation in a movement camp for children with
amputations
Feeling of security and self confidence in the
teacher
Online training of the coach
Application for personal training twice a week for 6
months (financed by a donation project and the
Elterninitiative) with follow-up registration at the
gym
Encouragement of the training by writing an exercise
plan to improve the basic endurance
Strengthening of social ties and self-esteem through
successful participation in the hiking trip of his
graduating class
Securing mobility through adapted bicycle
Participation and improvement of fitness through
weekly rowing at a club; sports-, nutritional, and
psychological counseling in the Care for
CAYAs-programme
Gathering of experiences in moving in outdoor sports
areas such as water, snow and climbing wall to
strengthen self-effectiveness and exchange with
other persons affected
Discussion
NAOK advisory approach to facilitate physical activity with a focus on
barrier management
NAOK-PAC aims to provide CAYAs with maximum support. Barriers and successdepend
on various factors such as the family system, local networks and offers, mode of
communication, and available time.
Problem dimensions
The difficulties that impede access to existing sports structures relate to three
main factors: a) family and socio-economic structures, and lack of b) a local
network and c) suitable sports programme.
Family and socio-economic structures include language barriers and severe
parental psychological and physical stress and thereof inability to
support their children financially or logistically (transportation,
sports wear, registration), despite several support initiatives existing
in Germany, such as “No child without sports” and “Education vouchers”.
Data on healthy CAYA confirms that children not participating in any
physical activity on a regular basis disproportionately come from
families with low social status, migration background, or from the new
federal German states [21 ].
Lacking a local network becomes apparent when CAYA are treated in clinics
where the NAOK-HQ is not able to offer a specific contact for
exercise-related questions. As a result, regional care, sports
activities, and personal assessments often fail, and possibly, the
results of motor performance tests cannot be obtained either
The lack of suitable sports programme primarily arises in structurally
weak and rural regions. These consultations are particularly
challenging, as small-town sports infrastructure usually leaves limited
choice. There often is a lack of sports facilities such as swimming
pools, fitness rooms or gyms as well as qualified professionals [22 ]. Existing clubs usually
offer only a few disciplines or a suitable club can only be reached by
traveling long distances. Regardless of where they live, CAYAs with
severe disabilities such as ataxia, amputation or physically impaired
performance generally have few options.
If several impeding factors accrue, the goals can only be attained through
personal commitment of professional staff or loved ones.
Intervention options
The issues that can make PAC more difficult are offset by three intervention
options fostering the NAOK-PAC’s success: a) approachable communication, b) a
wide network, and c) time available.
Approachable communication focuses on the CAYAs with their needs and
requirements, responding empathetically and individually. In the first
step, this includes a detailed anamnesis without time limit in a
personal (telephone) conversation, using simple language if necessary.
The communication structure in NAOK-PAC is resource-oriented, without
any pressure, and non-judgemental. The aim is to provide CAYAs with
confidence and to encourage them to persevere in achieving their
exercise goals with motivation and commitment.
A wide network consists primarily of staff of POC and sports programme.
This network plays a key role in providing PAC by conducting relevant
assessments, recommending local programme, finding inclusive and target
group-specific clubs, informing on camps and sports activities for CAYAs
with chronic diseases, and discussing critical case studies across
professions ([Table
2 ]).
Time is a key factor. NAOK-PAC is an established part of the NAOK-HQ and
is incorporated into the work space with a fixed-time quota. This
enables to provide advice and connections that can be tailored to
temporal needs, allowing creative solutions to be developed with
experts, such as the use of online options and intensive searching or
even the development of suitable programme.
Conclusion
Several studies underline the importance of PA during all phases of a (pediatric)
oncological treatment [23 ]
[24 ]. Looking for programs is often
overwhelming for patients and families. Fear of rejection and laborious search for
CAYAs-suitable programs often result in paralysization and despair. Therefore, the
process of intention to concrete action in CAYAs is questioned. This shows the
relevance of easily accessible and well-networked PAC, takin fears and needs
seriously, looking for suitable exercise options in a concept-led way, and
supporting families to get into action. Although awareness regarding the relevance
of regular engangement in exercise exists in many POC teams and this could also be
shown [18 ], it is currently impossible
to provide a complete set of supervised sports and exercise therapy and PAC for all
patients during medical treatment or follow-up care and to connect them to suitable
PA.
The NAOK-HQ provides a proven PAC concept, in addition to the specific integration of
individuals into PA programme. In the long term, it offering supervised sports and
exercise therapy and PAC alongside treatment for all individuals is intended.
Currently, 33 POC (55%) in Germany provide supervised sports and exercise therapy in
cooperation with the NAOK-HQ [25 ].
However, only a few of these have the time resources to provide comprehensive PAC.
To our knowledge, no published data exists on PAC concepts for chronically diseased
CAYAs. The NAOK-PAC concept introduces an explorative approach, focussing on
resource-oriented and individual support from a multidisciplinary network ([Fig. 1 ]).
In total, 200 CAYAs have been advised by PAC to date. The NAOK aims at promoting
physical, mental and social health through exercise [26 ]
[27 ] and increasing self-efficacy [28 ] for CAYAs. The case studies ([Table 2 ]) show that advice for CAYAs and adult patients differs [29 ]. Firstly, hardly any
oncology-specific sports groups exist. Secondly, equipment-guided and evidence-based
endurance and strength training [30 ],
rarely correspond to CAYAs needs. Thus, it is necessary to (1) jointly provide
creative and, if needed, customized solutions and (2) to use existing sports
structures. The opportunity to use the NAOK (free of charge) reliefs many families.
This support requires a well-founded and growing network ([Fig. 2 ]) as well as sustainability in
the employment of exercise professionals in POC.
Outlook
The NAOK-PAC programme needs to become even more well-known. Contact and
communication modes must be accessible more easily. Moreover, quality standards need
to be stated.
To enable communication, an online chat option should be added to the portfolio.
Furthermore, detailed documentation and follow-up of cases should be continuous to
enable adaptability and optimization. Long-term, the NAOK-PAC model is to be
implemented at the local NAOK POC and specifically adapted to each local
particularities. However, central networking should be maintained as individual
challenging issues often occur more frequently in decentralized settings.
In addition to advanced education courses in “Exercise therapy in paediatric
oncology” currently being developed by NAOK members, this concept paper provides a
base of knowledge basis and raises awareness of the relevance of PAC.
Cooperation and exchange with advisory structures in the context of other chronic
diseases, such as Mukoviszidose e.V. (https://www.muko.info/was-wir-tun/beratung-und-unterstuetzung/sportberatung ,
retrieved on XX.XX.2024), is recommended, taking into account similarity of
challenges and limitations in all pediatric patients. Even if the specific health
benefits cannot yet be confirmed here, the benefits in terms of participation in
sport are obvious. NAOK PAC is an innovative concept that enables nationwide access
to physical activity structures.
Contributor’s Statement
Contribution to study concept and design: G. Gauß, S. Kesting, J. Boos, M. Götte Data
collection: G. Gauss, D. Reinhard, M. Götte Data analysis and interpretation: G.
Gauss, S. Kesting, J. Boos, M. Götte Drafting the manuscript: G. Gauss, S. Kesting,
J. Boos, M. Götte Revising the manuscript: G. Gauß, S. Kesting, J. Boos, D.
Reinhard, M. Götte Letter to the editor: G. Gauß.
